The present invention relates to a supporting arm for the driving wheel of a vehicle comprising a suspension which oscillates by an angular motion of the arm about an axis connecting it to the body of the vehicle.
Suspensions of this type are now currently used in automotive vehicles, and the driving wheel is usually rotated by means of a shaft extending through the supporting arm and connected to a driving organ through a cardan or homocinetic joint allowing it to absorb the angular oscillations of the arm, which bring about variations of the length and the inclination of the shaft.
When it is desired to apply such a driving wheel suspension to a motor cycle, a solution is generally proposed, which consists in connecting the wheel to a supporting shaft mounted onto the arm by means of bearings, said supporting shaft being integral with a conical toothed crown wheel which is mechanically connected to the driving motor through a shaft supported by the arm and integral, in turn, with a conical pinion which meshes with the conical crown wheel.
An assembly of this kind is reliable, but the mechanical connections between the motor and the driving wheel are difficult to achieve and expensive.
It is thus one of the objects of the invention to provide a motor cycle rear driving wheel suspension assembly comprising a rotative supporting arm, this driving wheel being adapted to be driven by a chain, which constitutes up to now the most simple and reliable driving means for bicycles and motor cycles, since it is able to undergo comparatively large offsets and variations of the distance between the axes.